Ratchet-operating means



Jan. 11, 1949, W 2,459,008

RA'ICHE'I OPERATING MEANS Kfl IN VEN TOR.

li a /ferfl. Parse/1 Patented Jan. 11, 1949 UNITED STATES PATENT OFFICE,

- 2,459,008 RATCHET-LOPERATING MEANS 1 Walter; A. Tratsch, Chicago, Ill.Application J anuary 5, 1946, Serial No. 639,221

3 Claims.

This invention relates to certain novel improvements inratchet-operating means. More particularly the invention has for itsprincipal object the provision of means operable by the ratchetoperatingmeans for preventing retrograde or back-lash operationof the ratchetwheel.

The invention is especially useful in mechanisms which require apositive and limited step by step movement an operation which requiresfor its effective accomplishment the reduction of back-lashing to aminimum.

The mechanism to be hereinafter described has been shown in itsapplication in association with a coin-changing mechanism, in whichmechanism a conductor ring bearing shaft is rotated in step by stepaction into engagement with contact fingers controlling the circuit ofthe coin changer. It is customary to rotate this shaft by means .Of aratchet wheel through the operation of solenoids. In the employment ofsolenoids for this purpose, it infrequently happens that due to theimpingement of the push rods of the solenoids against the mechanism forrotating the ratchet wheel, there results what is known inthe trade asback-lashing of the ratchet wheel, or, in

other words, the ratchet wheel may have a tendency to rotate in aretroactive action to that intended. This invention has for its objectthe provision of means to prevent this back-lashing.

Other objects will appear hereinafter.

The invention consists in the. novel combina- Z tion and arrangement ofparts to be hereinafter I described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction, and in which:

Fig. 1 is a perspective view of a ratchet wheel having my inventionassociated therewith;

Fig. 2 is a perspective view similar to that shown in Fig. 1, taken at adifferent perspective invention are accomplished.

In this connection, for purposes of illustration I have shown a baseplate In having a mounting bracket ll associated therewith. Thismounting bracket l I may be connected to the base plate in any, suitablemanner. T-hismounting bracket ll comprising an upstanding wall l2.Journalled through this wall i2 is a shaft l3 having connection with asuitable coin changing mechanism M which comprises a conductor ring l5and contact fingers l6.

To this wall l2 there is secured inany suitable manner a support l'lsubstantially U-shaped and between the opposite limbs 18 of which aresupported magnetic solenoids I9, 20 and 2|. These solenoids eachcomprise a push rod 22, each push rod varying in length with respect tothe other for reasons hereinafter set forth.

On the shaft I3 is a ratchet wheel 23. Projectil'lg through the shaft i3is a stud shaft 25. On this stud shaft 25 is a sleeve 25 rotatableindependently of the shaft 25 and carrying an arm 25. This arm 26'pivotally carries as at 24 a pawl 26, the beak 21 of which normallyengages a pin 28 carried by the wall l2, whereby to support the pawl 26from engagement with the ratchet wheel 23. This ratchet wheel 23 iscarried by the shaft l3 and is rotatable therewith. The pawl 26 isnormally urged into engagement with the pin 28 and with the teeth of theratchet wheel 23 by a spring 30.

On the shaft 25 is an arm 3!, and this arm 3|,

at its outer end portion 32, has a lateral extension 33. Inwardly ofthis extension 33 and extending in an opposite direction with respectthereto is a second extension 34, and inwardly of this second extension34 and extending in opposite directions with respect thereto is a thirdextension 35. These extensions 33, 34, and 35 are disposed over the pathof the solenoid push rods 22. The push rod of the solenoid I9, for thepurposes of illustration, is shorter in length than the other two pushrods, with the consequence that when the solenoid I9 is energized, theshaft will be rotated so as to-bring the pawl 26 into engagement withthe ratchet wheel 23 to move it a distance equivalent to one tooth ofthe ratchet wheel 23. As the push rod of the solenoid 20 is longer thanthe push rod of the solenoid H), but shorter than the push rod of thesolenoid 2 I, it is manifest that upon energization of the solenoid 20,the push rod 22 thereof, upon engagement with the adjacent extension 35,is arranged to engage the pawl 26 with the ratchet wheel 23, so as tomove the ratchet wheel a distance equivalent to two teeth of the ratchetwheel. Upon energization of the solenoid 2|, the push rod of which islonger than either of the push rods of the solenoids I9 and 20, when thepawl 26 is brought into engagement with the ratchet wheel 23, theratchet wheel 23 will be rotated a distance equivalent to three teeth ofthe ratchet wheel.

To prevent any back-lashing or retroactive rotation of the ratchet wheel23 in a direction opposite to that of its rotation by action of the pawl26, there is arranged a latch bar 36 movable vertically through openings31 provided in the portions [8 of the bracket H. The lower end portionof this latch bar 36 carries an enlarged collar 38 between which and theadjacent portion I8 of the bracket ll "is aspringsratr whi'ch'rnormal-lyholds .thewlatchebar' -36 from engagement-with the teeth of the ratchet23. Each of the push rods 22 of the solenoids I9, and 2| have their endportions 40 extending below ..the...solenoi.ds I 9, 20 and 2!, and theseend portionsncarry-en-- larged discs 4! which are adaptedtoengagwthecollar 38 as shown in Fig. 4, and move the latch bar 36 in an elevatedposition-with the horizontal" portion 42 thereof into engagementwitlnatooth of the ratchet wheel 23. This horizontal portion 42 operatesthrough an elongated slot '43,.formed inithe wall I2(Fig. 4).

"To complete the invention, Iprovidera, reset coil 44 which includes asolenoid .push rod 45 adapted to engage the arm 46 of an 'escapement:pawlfl;thearrangement being such that when the ratchet. 23 hasbeenwound to apredetermined position, against the action of'thespring'AB, upon energization of the reset coil 44, the escapement pawlwill permit retroactive rotation of the ratchet 23'to its normal,position.

. As shown .in Fig. 1, {the arm 3| is normally held in position forengagement bythe pushrods "22', by a spring '48.

The arrangement issuch that when one of "the. solenoids, for'example,the solenoid L9, is energized, the. push rod 22 thereof will moveupwardly against the adjacent extension 34,. and

this engagement between the push rod 22and'the extension 34 willrock theshaft 25, disengaging .the tip.or beak 21,. of .the pawl 26 fromjthe pin28, allowing this pawl to drop into engagement with the .ratchetwheel.23, and thus "moving the ratchet wheel one'step or a distance equivalentto one of the teeth of the ratchet. Whenjthis push rod 22 reachesitsuppermostposition"with "respect to the solenoid coil 19,.thedisc"flFthereof will engage the'collar'38, move-theflatch' bar'flfi intolatched engagement with the ratchet 23 and momentarily latch thisratchetiwheel: 23"against a shaft, a ratchet wheel on theshaftifori-rrotation therewith, a pawl movable into engagement with theratchet wheel for rotating the latter step by step, means for moving thepawl into engagement with the rachet wheel, means operable by thepawl-moving means and operatively related to the ratchet Wheel to latchthe ratchet wheel against rotation in a direction opposite to therotation thereof by the pawl, said pawl-moving smeanswinclnding asleevvmountedon the shaft .foriindepend'ent rotation thereof, meanspivotally connecting the pawl to the sleeve, an arm carried oby thesleeve and having lateral extensions .formedtherein, and independentlyoperated sole- "-n'oids-"having push rods adapted to engage saidmeertensions.

2. Mechanism of the class described including ashaa, a=ratchet whee1 onthe shaft for rotation therewith, a pawl movable into engagement withthe ratchet wheel for rotating the latter step by step, means formovingthe, pawl into engagement Withfthe .ratch'et Wheel, said pawl-movingmeans ..including,a;sleeve mounted on the shaftfor independentrotationthereof, means pivotally con- .nectingfthepawl to the sleeve, anarm carried by "the sleeve .,and having lateral extensions formedtherein, independently, operated solenoids ihavingwpushrods adapted. to.engage said extensionsl'latfch means for. latching. the ratchet wheelragainst rotation..irl,.a=fdirection opposite to the direction ofrotation ofjtheratchet Wheel-by the pawl, said .latchmreans. includingan end,v portion having ranuenlargedcollar, and disc. elements car .riedLby1 'the-.,push .rodsand .adapted to engage said ,collanwhen saidpushrods are moved in one "direction. v

T Mechanismeof ,the class described for latche ing a. ,rat'chetWheel-and.a shaft against rotation in-one "direction, and which shaft. andratchet .Whel .arei rctatedstep .by step in an opposite .direc'tiortby.solenoid actuating means, comprising .a structure supporting saidsolenoid actuat- .ing. means, aumember. carried by said structureand...movable -in .the direction of .its length by said, solenoidactuating.,means and having an an.- ja 'led end, portion adapted f orengagement with the ratchet lwheel..to,.latch the ratchet wheel.againstrotationin ardirectionopposite to the rota'tion lthereofebysaidsolenoid actuating :means andhaving -anvppposite ..end. :portionengageable by.an .lement.ofasaid solenoid actuating means for. movingsaid. member inusaid direction with respect 'to its length to disposeithe angledend portion intdengagementwith said ratchet wheel.

.-WA LTER. A. TRATSCH.

' "REFERENCES .CITED Thedbllowing references are of record inthe flier:0f: ithisiipatent:

STATES PATENTS 1Adams July 21, 1914

